1. Field of the Invention
The present invention relates to an optical transmission deflector in which light is deflected by a prism which is mechanically driven via electromagnetic operation.
2. Description of the Related Art
There are two types of optical deflectors known in which a mirror which is adapted to deflect light is reciprocally moved or the mirror is rotated. The use of a galvano mirror is one typical way of providing an optical deflector, wherein the mirror is reciprocally moved. The use of a polygonal mirror is another way of providing an optical deflector, wherein the mirror is rotated. However, there is no transmission type optical deflector known hitherto. In theory, a transmission deflector can be realized, for example, by the employment of a wedge-shaped prism in place of the galvano mirror. However, no transmission deflector has been actually practiced. This is because, firstly, a wedge-shaped prism is heavier than a planar mirror, and secondly, the position of the center of gravity of the prism varies depending on the shape thereof, and hence oscillation tends to occur due to a weight imbalance, thus leading to difficulty in realizing a precise and fast-driven optical deflector.